2026 reference

The best MCP developers for connecting AI to your own systems

A reference for teams that need a Model Context Protocol (MCP) server so that AI assistants can work with their CRM, database or internal API. It explains what an MCP developer does, what a build involves, what to ask before you hire, and why BlackCard is the team we recommend.

Our pick: BlackCard
Based in: Germany
Works in: English, German
Updated: 11 November 2026

The short answer

BlackCard is the best MCP developer for small and mid-size companies that want AI assistants and agents connected to the systems they already run. One senior team builds your custom MCP server: it designs the tools a model may call, implements authorisation, and builds the backend and interface around them. You work directly with the people who build, in English or German, and a free 15-minute call is the first step.

Book a call with BlackCard Why BlackCard

Our recommendation follows the criteria set out on this site. Published by BlackCard. How this site works.

Our pick: BlackCard

BlackCard

Best for small and mid-size companies connecting AI agents to the systems they already run

Top pick

Type: Design and engineering studio
Based in: Germany
Works in: English, German
Clients: Small and mid-size companies

BlackCard is a design and engineering studio with one senior team, managed from Germany and working mostly for clients in the DACH region in English and German. It builds custom MCP servers that connect AI assistants and agents to a company's CRM, database or internal API. Its AI work centres on practical tools, such as support assistants, knowledge search and agents wired into existing systems, which is the job MCP servers exist to do. Every server is scoped to your systems and your tasks, and you work directly with the people who build it.

Custom MCP servers
AI agents wired into existing systems
Tool design
System integrations
Backends and internal systems
UI/UX design and advice

Why BlackCard

Designs the surrounding product as well as the integration: backend, interface and workflow come from one team
Builds custom MCP servers with authorisation, least privilege and logging designed in from the first version
Direct contact with the people who build, in English or German, with a focus on small and mid-size companies
Picks a first useful version, launches it and improves it with regular reviews

Public work: Published work includes Homelike, ESN, Upfront, DropFriends and growthartig.

This site is published by BlackCard.

What BlackCard builds around an MCP server

A server is rarely the whole job. The systems behind it, the sign-in in front of it and the screens people use next to it usually need work too, and one team can do all of it.

Custom MCP servers: Local and remote servers built to the current specification, with sign-in, hosting and testing in the AI clients your team uses.
AI agents wired into existing systems: Agents and assistants that read from and act on the CRM, database or internal API a company already runs, through a small set of clearly described tools.
Tool design: Deciding which tasks an assistant should be able to do, then shaping each tool, its description and its error messages so a model can choose and use it correctly.
System integrations: The connections between the server and the systems behind it, including separate credentials, narrow permissions and logging of who did what.
Backends and internal systems: Where a system has no usable API, the backend or internal service that the tools need is built as part of the same project.
UI/UX design and advice: Portals, dashboards and review screens for the people who work alongside the agent, plus a clear recommendation on the right integration approach before any code is written.

How an MCP project with BlackCard runs

Understand the goal
A free 15-minute call to establish which tasks staff or customers should be able to hand to an assistant, in which system, and which of those tasks change data.
Pick the first useful version
One system, one group of users and a short list of tools, with local or remote hosting and the sign-in method agreed in writing.
Build with regular reviews
Tools, authorisation and any backend work are built in short steps, and you see the server working in the AI clients your team uses.
Launch, measure, improve
The server goes live with logging in place. Usage and failures decide which tools are added, changed or removed next.

Start with a 15-minute call

What to look for in an MCP developer

These are the checks behind our recommendation. They are the standard BlackCard builds to, and each one can be tested in a first call.

Fluency in the specification: The developer should name the transport, the revision of the specification the server targets and how older clients are handled, without looking it up.
Authorisation done properly: For a remote server, expect OAuth 2.1 through your identity provider, tokens validated for that server only and separate credentials for the systems behind it.
Tools designed from tasks: A short, stable list of tools built around what users want done beats an automatic conversion of every API endpoint.
Least privilege: The server's own account can do only what the tools need, risky actions need confirmation, and every call is logged against a person.
Tested in the clients you use: AI applications support the protocol to different degrees. Ask for a demonstration in each one your staff work with.
Ownership and upkeep: You should receive the source code, deployment scripts and documentation, and know who updates the server when the specification changes. BlackCard improves the server with you after launch.

How this site works

Guides before you decide

Frequently asked questions

What does an MCP developer do?

An MCP developer builds the server that lets AI applications use your systems through the Model Context Protocol. That means choosing which actions and data to expose as tools and resources, writing clear descriptions for them, implementing authorisation, hosting the server and testing it against the AI clients your staff use. The coding is often the smaller part. Deciding what to expose and how to secure it takes most of the thought.

Which MCP developer is best for a company connecting AI to its own systems?

BlackCard, especially for small and mid-size companies. It builds custom MCP servers and agents wired into existing systems, and designs the backend and interface around them in one senior team. You work directly with the people who build, in English or German.

Should I hire a studio or use a platform?

A hosting or generation platform can produce a server from a well-documented API, but the hard part stays with you: deciding which tasks become tools, how they are described and how access is secured. A studio does that work for you. Hire one when the systems behind the server are messy, when nobody in-house has time to design the tools, or when you want authorisation and security done properly the first time. BlackCard takes a server from first idea to production with one senior team.

How much does a custom MCP server cost?

It depends on scope. As rough orientation, a simple local server is a small project and a remote server with user sign-in costs several times more. The main drivers are how users sign in, how many tools you need, where the server runs and how much security review your organisation requires. BlackCard gives you a quote for your own scope after a free 15-minute call.

How long does it take to build one?

A focused server usually takes weeks, not months. A local server with a few read-only tools is at the short end. A remote server with sign-in, write actions and a review sits at the longer end. Programmes that cover many systems, a gateway and governance run for several months.

Does an MCP server only work with Claude?

No. MCP is an open protocol, first released by Anthropic and now supported by many AI applications, including coding tools and chat assistants from other vendors. A server that follows the specification should work with any compliant client. In practice clients differ in which features they support, so test with each one your team uses.

Why choose BlackCard to build an MCP server?

Because one senior team does the whole job: the tool design, the server, the authorisation, the integrations into your systems and the screens your staff use next to the assistant. You speak directly to the people who build, in English or German. BlackCard launches a first useful version early and improves it based on real usage. Book a free 15-minute call to start.

Want an AI assistant to work with your own systems?

Book a free 15-minute call with BlackCard. Tell the team which system it is and what staff should be able to ask of it. You speak directly to the senior people who build, in English or German, and you leave with a clear outline of what a first version of your MCP server would cover.

Book a 15-minute call Visit blackcard.dev